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The leaves of many palm species represent important non-timber forest products (NTFPs), which may be intensively harvested by local people in many tropical areas. Additionally, in some regions livestock graze in natural forests, and they may browse on palm leaves, especially during the dry season. Thus, harvesting and browsing can result in the loss of leaf area of individual palms, which may alter functional traits of individuals and change demographic patterns of populations. Currently, there are few studies that analyze the effects of multiple disturbances on these traits. The goals of this study were to evaluate the effects of browsing, leaf harvesting and the interaction between these two factors on individual traits and demographic patterns of the palm in northwestern Mexico. A browsing and leaf harvesting experiment was conducted on natural populations of the species. Individuals were subjected to different harvesting intensities and the presence or absence of cattle. Annual censuses were conducted from 2011 to 2014, and individual traits (leaf length, petiole length, and leaf production) and vital rates were monitored. At the individual level, the analyzed traits mostly increased as function of leaf harvest and browing, especially during the first two years. Palms experiencing leaf harvesting and browsing had 1.5 to 6.0 times higher levels of leaf production than control palms, especially juveniles and small adults. At the demographic level, the effects of browsing and leaf harvest were low or null, since survival was not affected by them. Browsing positively affected the growth of individuals in the first 2 years, while leaf harvesting had a negative effect in year three. There was a positive relationship between the probability of reproduction and leaf harvest; however, high leaf harvest resulted in two to three times fewer fruits produced. After 3 years of experimental management, multiple of the analyzed attributes decreased, suggesting that changed patterns of resource allocation. Based on our results, can be considered a species that tolerates high levels of defoliation and browsing for 2 years, but not likely longer. This study contributes basic ecological information useful for the conservation and management of , but overall it also highlights that different anthropogenic activities may act as drivers affecting the functional response and demography of NTFP species and they should be considered for the long-term integral management of these species.

G-protein-coupled receptors (GPCRs) transduce physiological and sensory stimuli into appropriate cellular responses and mediate the actions of one-third of drugs. GPCR structural studies have revealed the general bases of receptor activation, signaling, drug action and allosteric modulation, but so far cover only 13% of nonolfactory receptors. We broadly surveyed the receptor modifications/engineering and methods used to produce all available GPCR crystal and cryo-electron microscopy (cryo-EM) structures, and present an interactive resource integrated in GPCRdb (http://www.gpcrdb.org) to assist users in designing constructs and browsing appropriate experimental conditions for structure studies.An interactive online resource integrated in the GPCRdb hub presents tools to design GPCR constructs and determine appropriate experimental conditions for structural studies by crystallography and cryo-EM.

Management of tree cover, either to curb bush encroachment or to mitigate losses of woody cover to over-browsing, is a major concern in savanna ecosystems. Once established, trees are often “trapped” as saplings, since interactions among disturbance, plant competition, and precipitation delay sapling recruitment into adult size classes. Saplings can be directly suppressed by wildlife browsing and competition from adjacent plants, and indirectly facilitated by grazers, such as cattle, which feed on neighboring grasses. Yet few experimental studies have simultaneously quantified the effects of cattle and wildlife on sapling growth, particularly over long time scales. We used a series of replicated 4-ha herbivore-manipulation plots to investigate the net effects of wildlife and moderate cattle grazing on Acacia drepanolobium sapling growth over 10 years that encompassed extended wet and dry periods. We also simulated more intense cattle grazing using grass removal treatments (0.5-m radius around saplings), and we quantified the role of intraspecific tree competition using neighborhood tree surveys (trees within a 3-m radius). Wildlife, which included elephants, had a positive effect on sapling growth. Wildlife also reduced neighbor tree density during the 10-yr study, which likely caused the positive effect of wildlife on saplings. Although moderate cattle grazing did not affect sapling growth, grass removal treatments simulating heavy grazing increased sapling growth. Both grass removal and neighbor tree effects on saplings were strongest during above-average rainfall years following drought. This highlights that livestock-driven reductions in grass cover and catastrophic wildlife damage to trees during droughts present a need, or an opportunity, for targeted management of sapling growth and woody plant cover during ensuing wet periods.

The objective of this study was to evaluate the damage caused to trees by beef cattle in integrated crop-livestock-forestry (ICLF) systems with different tree arrangements. The treatments evaluated were the ICLF-1L system, with single lines of eucalyptus (187 trees ha−1), and the ICLF-3L system, with three lines of eucalyptus (446 trees ha−1). The experimental design consisted of randomized blocks with four replications. The eucalyptus clone I-224 and Nellore cattle breed were used for this study. The damage caused by cattle to eucalyptus was classified as follows: Tb, trunk breakage; Ti, trunk injury reaching the wood by removing the cambium tissue; Bb, breakage branches greater than 2 cm in diameter; Bi, bark injury without reaching the cambium; Bt, breakage of thin branches and browsing on leaves; and Di, lesions greater than 5 cm in diameter. The damage score was calculated for each tree by the sum of grade the damage that cattle caused to the tree: Tb = 10.0; Ti = 4.0; Bb = 2.0; Bi = 1.5; Bt = 1.0; and Di = 1.0. The diameter at breast height (DBH), height and wood volume of the trees were also evaluated. The frequencies of Ti, Bb and Di were greater in the ICLF-1L system than in the ICLF-3L system (P < 0.05); in contrast, the frequencies of Bt and Bi were greater in the ICLF-3L system. The damage score was greater in the ICLF-1L system (6.61; P < 0.05) than in the ICLF-3L system (4.60). The height was greater in the ICLF-3L system (P < 0.05), and the DBH and individual wood volume did not differ between the systems (P > 0.05). Cattle cause damage to eucalyptus trees regardless of tree arrangement (ICLF-1L and ICLF-3L), but the damages were greater in the ICLF-1L system. Although the damages were more severe in ICLF-1L, tree growth and wood production were the same in both systems. Additional studies should be conducted to assess the impacts of livestock damage in wood quality.

There is a long lasting debate on the effects of domestic cattle grazing on natural ecosystems worldwide. Cattle are generally assumed to have negative effects on forest conservation; however, several studies also report positive and neutral effects. We aimed to investigate the available evidence for positive, negative and neutral effects of cattle grazing on forest and woody ecosystems of southern South America. We conducted a peer-review literature search using the ISI Web of Knowledge and Scopus databases to identify studies dealing with cattle impacts for nature conservation. We compiled a database of 211 cases from 126 original publications. A reduced number of forest ecosystems (Patagonian forest, Chaco and Monte) concentrated ~ 85% of the reported study cases. The hierarchical cluster analysis to group cases based on cattle effects, ecological variables and ecosystems reported that negative effects (~ 66% of cases) were mostly informed for vegetation variables and mainly occur in Patagonian forest and Chaco; positive effects (∼16 %) were mostly informed for Monte (no particular variable associated), while neutral effects (∼ 18 %) were mostly informed for fauna-related variables and Uruguayan savanna. Our study suggests that grazing effects by cattle on southern South America forests are not homogeneous and depend on the particular forest ecosystem considered as well as on the forest attribute measured. Different cattle effects found can be partially explained by differences in grazing history and different ecosystems productivity. It is vital to improve our understanding of cattle–forest interactions to guide synergies between sustainable management and forest conservation.

In many savanna ecosystems worldwide, livestock share the landscape and its resources with wildlife. The nature of interactions between livestock and wildlife is a subject of considerable interest and speculation, yet little controlled experimental research has been carried out. Since 1995, we have been manipulating the presence and absence of cattle and large mammalian herbivore wildlife in a Kenyan savanna in order to better understand how different herbivore guilds influence habitat use by specific wildlife species. Using dung counts as a relative assay of herbivore use of the different experimental plots, we found that cattle had a range of effects, mostly negative, on common mesoherbivore species, including both grazers and mixed feeders, but did not have significant effects on megaherbivores. The effect of cattle on most of the mesoherbivore species was contingent on both the presence of megaherbivores and rainfall. In the absence of megaherbivores, wild mesoherbivore dung density was 36% lower in plots that they shared with cattle than in plots they used exclusively, whereas in the presence of megaherbivores, wild mesoherbivore dung density was only 9% lower in plots shared with cattle than plots used exclusively. Cattle appeared to have a positive effect on habitat use by zebra (a grazer) and steinbuck (a browser) during wetter periods of the year but a negative effect during drier periods. Plots to which cattle had access had lower grass and forb cover than plots from which they were excluded, while plots to which megaherbivores had access had more grass cover but less forb cover. Grass cover was positively correlated with zebra and oryx dung density while forb cover was positively correlated with eland dung density. Overall these results suggest that interactions between livestock and wildlife are contingent on rainfall and herbivore assemblage and represent a more richly nuanced set of interactions than the longstanding assertion that cattle simply compete with (grazing) wildlife. Specifically, rainfall and megaherbivores seemed to moderate the negative effects of cattle on some mesoherbivore species. Even if cattle tend to reduce wildlife use of the landscape, managing simultaneously for livestock production (at moderate levels) and biodiversity conservation is possible.

1. We tested the interactions between biotic and abiotic factors in structuring temperate forest communities by comparing tree recruitment after 7 years inside 30 pairs of exclosure (excluding ungulates: red deer, roe deer, bison, moose, wild boar) and control plots (7 x 7 m each) in one of the most natural forest systems in Europe, the Białowieża Primeval Forest (eastern Poland). The strictly protected part of that forest hosts the complete native variety in trees, ungulates and their carnivores and excludes human intervention. 2. We analysed whether the exclosure effect interacted with abiotic factors, relevant for tree recruitment (canopy cover, ground vegetation cover, soil fertility and soil wetness) at different stages of tree regeneration (seedlings, saplings [less-than or equal to] 50 and > 50 cm). 3. Contrary to our expectations, a single factor dominated at each stage of tree regeneration. Herbaceous vegetation cover was the main factor determining the number of seedlings with an optimum at 38% of cover. Soil fertility determined the density of saplings [less-than or equal to] 50 cm, with on average three times higher density on eutrophic than on oligotrophic soils. Herbivory was the main factor determining recruitment rate of trees into > 50 cm size classes only. 4. The density of saplings that grew into the > 50 cm size class was more than three times higher in the exclosures than in the control plots during 7 years. In the absence of ungulates, on average 3.1 species recruited into the > 50 cm size class compared to 1.7 in control plots. Tree species occurred in more equal proportions inside exclosures, whereas species composition was pushed towards strong dominance of a preferred forage species, Carpinus betulus, in the presence of ungulates. This suggests that preference of species by ungulates can coincide with tolerance to browsing. 5. Synthesis. The study showed that abiotic conditions dominated the early stages and ungulate impact the later stages of tree regeneration, indicating the context-dependence of herbivore top-down effects. Heterogeneity in abiotic and biotic conditions may, therefore, have an important influence on the strength of top-down effects and the role that herbivores play in natural ecosystems.

Questions: Ungulate herbivory and formation of large termite mounds occur over different time scales, but both can affect plant community composition in savannas. Human-managed savanna systems are increasingly dominated by domesticated grazing herbivores. These have replaced a mix of indigenous browsers and grazers, leading to changes in plant communities such as increased bush encroachment. We compared the relative impacts of five decades of different types of ungulate herbivory (cattle grazing, browsing and grazing by wild herbivores, and exclusion of all larger herbivores) on woody plant assemblages in two habitats, namely, large termite mounds, which may be thousands of years old, and the surrounding matrix. Location: Miombo woodland savanna, Zimbabwe. Methods: To determine the influence of termite mounds and herbivory on spatial distribution and composition of woody assemblages, we compared 40 paired mound-matrix plots from the three herbivory treatments using PERMANOVA. We assessed whether mound plots were more similar to each other than matrix plots were to each other, and whether herbivory influenced similarity. We used SIMPER analysis to identify changes in abundance of indicator species for each habitat (i.e. mound or matrix). Results: Species composition differed significantly between mound and matrix and also between herbivory treatments. Woody plant assemblages on mounds were more similar to each other than woody plant assemblages in matrix plots were to each other, regardless of type of herbivory, but herbivory reduced the mound/matrix contrast. Sample location (i.e. on mound or in matrix) explained 23% of the variation in woody species composition, compared to 12% explained by herbivory. Woody plant abundance was lowest where there were both grazers and browsers. Conclusions: The influence of large termite mounds on plant assemblages was roughly double that of herbivory, which has occurred over five decades. Type of herbivory emerged as relatively influential on woody plant species composition, given that the time periods involved were short by comparison to the slow formation of termite mounds. Type of herbivory also influenced species composition and vegetation structure, with a diversity of herbivores necessary to reduce encroachment by woody species.

The Bronze Age village of Politiko- Troullia , located in the foothills of the copper-bearing Troodos mountains of central Cyprus, was occupied ~2050–1850 cal BCE. Excavated evidence shows that community activities included copper metallurgy (ore processing, smelting and casting), crop cultivation, and rearing of livestock. Faunal analysis reveals day-to-day subsistence practices that included consumption of sheep, goat, cattle, and pig, as well as community-scale ritual feasting focused on fallow deer, Dama dama mesopotamica . In this paper, we present bone collagen stable isotope data from these taxa to infer how these animals were managed. We incorporate stable isotope baselines calculated from modern cereal grains and compare these to archaeological seeds from Politiko- Troullia . Mean values of δ 13 C and δ 15 N cluster for livestock consistent with a diet of C3 plants, with a wider range in goats that suggests free-browsing herds. Higher δ 15 N values in cattle may reflect supplemental feeding or grazing in manured fields. Plant isotope values suggest livestock diets were predominantly composed of cultivated taxa. In contrast, deer and pig bones produce more negative mean δ 13 C and δ 15 N values suggesting that the villagers of Politiko- Troullia complemented their management of domesticated animals with hunting of wild deer and feral pigs in the woodlands surrounding their village.

1. Savanna tree cover is dynamic due to disturbances such as fire and herbivory. Frequent fires can limit a key demographic transition from sapling to adult height classes in savanna trees. Saplings may be caught in a 'fire trap', wherein individuals repeatedly resprout following fire top-kill events. Saplings only rarely escape the cycle by attaining a fire-resistant height (e.g. taller than the minimum scorch height) during fire-free intervals. 2. Large mammalian herbivores also may trap trees in shorter size classes. Browsing herbivores directly limit sapling height, while grazing herbivores such as cattle facilitate sapling growth indirectly via grass removal. Experimental studies investigating how meso-wildlife, megaherbivores and domestic livestock affect height of resprouts following fire are rare, but necessary for fully understanding how herbivory may reinforce (or counteract) the fire trap. In our study system, interactive fire-herbivore effects on transitions from sapling (<1 m) to adult tree (>1 m) height classes may be further influenced by plant defences, such as symbiotic ants. 3. We used the Kenya Long-term Exclosure Experiment (KLEE) to investigate how post-fire resprout size of a widespread monodominant East African tree, Acacia drepanolobium was influenced by (a) herbivory by different combinations of cattle, meso-wildlife (15-1,000 kg) and megaherbivores (>1,000 kg) and (b) the presence of acacia-ant mutualists that confer tree defences. We sampled height, stem length and ant occupancy of resprouts exposed to different herbivore combinations before and after controlled burns. 4. Resprout height of saplings that were short prior to fire (<1 m) was reduced primarily by meso-wildlife. Negative effects of elephants on post-fire resprout height increased with pre-fire tree size, suggesting that resprouts of the tallest trees (with the greatest potential to escape the fire trap cycle) were preferentially browsed and reduced in height by elephants. There were no significant cattle effects. 5. Synthesis. We provide experimental evidence for two potential pathways through which large herbivores exert control over sapling escape from the fire trap: (a) post-fire meso-wildlife browsing of short (<1 m) resprouts and (b) elephant browsing of the largest size class of resprouts, which would otherwise be most likely to escape the fire trap.